中文摘要：

文章运用2000年第五次及2010年第六次人口普查数据,对兰州市主城区老龄人口的空间分布及其形成机制进行了分析。结果表明：兰州市老龄人口增速快,各区增长差异显著,街区差距相对缓和;老龄人口比重呈圈层结构分布,街区间比重差异明显,老龄人口高密度街区范围扩大,空间特征呈现出明显的＂双中心＂结构;高龄老人增速快,老龄人口性别比下降,空巢家庭日益增加,老年抚养负担加重。其形成机制主要缘于历史沿革、社会发展、人口生育政策以及人口迁移的共同作用。

英文摘要：

With the rapid development of the urban economy and society, the appearance of the aging phenomenon was becoming an inevitable result gradually. Aging of the population has become one of the major issues and has received increasing attention. Under such situations, this paper analyzes the spatial distribution characteristics and formation mechanisms of the elderly population in Lanzhou based on the fifth census data in 2000 and the sixth census data in 2010. The results showed that： in terms of the space growth of elderly, elderly population in Lanzhou City increased with rapid speed, the population growth difference among municipal districts was significant, and the gap was relatively moderate between blocks. From the angle for the spatial distribution, the proportion of elderly population presents an obvious layered spatial structure and the crest value center of proportion became multicenter. The proportion of elderly keeps growing and that the differences were significant in proportion between blocks. The number of high elderly population density blocks was increasing and the area was expanding. The gap was relatively moderate between blocks, and the overall trend of elderly population distribution shows a space structure of＂double columnar peak body＂,which was consistent with the structure of overall population in Lanzhou. In the aspect of internal structure,the oldest old increased with rapid speed, and the age structure constantly aging at the same time. Moreover,while the sex ratio of elderly population was declined, the sex ratio of oldest old was ascended. Meanwhile,the number of empty- nest families was increased, and the burden of elderly support was aggravated. As a whole, the revolution is under combined influences of history, society development rule, policy of fertility and population migration.